/**
 * Provides the language utilites used by the library
 * @class ISS.lang
 * 
 * Modified from YAHOO.lang
 */
ISS.lang = ISS.lang || {};

(function() {
	var L = ISS.lang,

	OP = Object.prototype,
    ARRAY_TOSTRING = '[object Array]',
    FUNCTION_TOSTRING = '[object Function]',
    OBJECT_TOSTRING = '[object Object]',
    NOTHING = [],

    // ADD = ["toString", "valueOf", "hasOwnProperty"],
    ADD = ["toString", "valueOf"],

	OB = {

	    /**
	     * Determines wheather or not the provided object is an array.
	     * @method isArray
	     * @param {any} o The object being testing
	     * @return {boolean} the result
	     */
	    isArray: function(o) { 
	        return OP.toString.apply(o) === ARRAY_TOSTRING;
	    },

	    /**
	     * Determines whether or not the provided object is a boolean
	     * @method isBoolean
	     * @param {any} o The object being testing
	     * @return {boolean} the result
	     */
	    isBoolean: function(o) {
	        return typeof o === 'boolean';
	    },
	    
	    /**
	     * Determines whether or not the provided object is a function.
	     * Note: Internet Explorer thinks certain functions are objects:
	     *
	     * var obj = document.createElement("object");
	     * ISS.lang.isFunction(obj.getAttribute) // reports false in IE
	     *
	     * var input = document.createElement("input"); // append to body
	     * ISS.lang.isFunction(input.focus) // reports false in IE
	     *
	     * You will have to implement additional tests if these functions
	     * matter to you.
	     *
	     * @method isFunction
	     * @param {any} o The object being testing
	     * @return {boolean} the result
	     */
	    isFunction: function(o) {
	        return (typeof o === 'function') || OP.toString.apply(o) === FUNCTION_TOSTRING;
	    },
	        
	    /**
	     * Determines whether or not the provided object is null
	     * @method isNull
	     * @param {any} o The object being testing
	     * @return {boolean} the result
	     */
	    isNull: function(o) {
	        return o === null;
	    },
	        
	    /**
	     * Determines whether or not the provided object is a legal number
	     * @method isNumber
	     * @param {any} o The object being testing
	     * @return {boolean} the result
	     */
	    isNumber: function(o) {
	        return typeof o === 'number' && isFinite(o);
	    },
	      
	    /**
	     * Determines whether or not the provided object is of type object
	     * or function
	     * @method isObject
	     * @param {any} o The object being testing
	     * @return {boolean} the result
	     */  
	    isObject: function(o) {
	    	return (o && (typeof o === 'object' || L.isFunction(o))) || false;
	    },
	        
	    /**
	     * Determines whether or not the provided object is a string
	     * @method isString
	     * @param {any} o The object being testing
	     * @return {boolean} the result
	     */
	    isString: function(o) {
	        return typeof o === 'string';
	    },
	        
	    /**
	     * Determines whether or not the provided object is undefined
	     * @method isUndefined
	     * @param {any} o The object being testing
	     * @return {boolean} the result
	     */
	    isUndefined: function(o) {
	        return typeof o === 'undefined';
	    },
	    
	    /**
	     * Utility to set up the prototype, constructor and superclass properties to
	     * support an inheritance strategy that can chain constructors and methods.
	     * Static members will not be inherited.
	     *
	     * @method extend
	     * @static
	     * @param {Function} subc   the object to modify
	     * @param {Function} superc the object to inherit
	     * @param {Object} overrides  additional properties/methods to add to the
	     *                              subclass prototype.  These will override the
	     *                              matching items obtained from the superclass 
	     *                              if present.
	     */
	    extend: function(subc, superc, overrides) {
	        if (!superc||!subc) {
	            throw new Error("extend failed, please check that " +
	                            "all dependencies are included.");
	        }
	        var F = function() {}, i;
	        F.prototype=superc.prototype;
	        subc.prototype=new F();
	        subc.prototype.constructor=subc;
	        subc.superclass=superc.prototype;
	        if (superc.prototype.constructor == OP.constructor) {
	            superc.prototype.constructor=superc;
	        }
	    
	        if (overrides) {
	            for (i in overrides) {
	                if (L.hasOwnProperty(overrides, i)) {
	                    subc.prototype[i]=overrides[i];
	                }
	            }
	        }
	    },
	   
	    /**
	     * Applies all properties in the supplier to the receiver if the
	     * receiver does not have these properties yet.  Optionally, one or 
	     * more methods/properties can be specified (as additional 
	     * parameters).  This option will overwrite the property if receiver 
	     * has it already.  If true is passed as the third parameter, all 
	     * properties will be applied and _will_ overwrite properties in 
	     * the receiver.
	     *
	     * @method augmentObject
	     * @static
	     * @since 2.3.0
	     * @param {Function} r  the object to receive the augmentation
	     * @param {Function} s  the object that supplies the properties to augment
	     * @param {String*|boolean}  arguments zero or more properties methods 
	     *        to augment the receiver with.  If none specified, everything
	     *        in the supplier will be used unless it would
	     *        overwrite an existing property in the receiver. If true
	     *        is specified as the third parameter, all properties will
	     *        be applied and will overwrite an existing property in
	     *        the receiver
	     */
	    augmentObject: function(r, s) {
	        if (!s||!r) {
	            throw new Error("Absorb failed, verify dependencies.");
	        }
	        var a=arguments, i, p, overrideList=a[2];
	        if (overrideList && overrideList!==true) { // only absorb the specified properties
	            for (i=2; i<a.length; i=i+1) {
	                r[a[i]] = s[a[i]];
	            }
	        } else { // take everything, overwriting only if the third parameter is true
	            for (p in s) { 
	                if (overrideList || !(p in r)) {
	                    r[p] = s[p];
	                }
	            }
	        }
	    },
	 
	    /**
	     * Same as ISS.lang.augmentObject, except it only applies prototype properties
	     * @see ISS.lang.augmentObject
	     * @method augmentProto
	     * @static
	     * @param {Function} r  the object to receive the augmentation
	     * @param {Function} s  the object that supplies the properties to augment
	     * @param {String*|boolean}  arguments zero or more properties methods 
	     *        to augment the receiver with.  If none specified, everything 
	     *        in the supplier will be used unless it would overwrite an existing 
	     *        property in the receiver.  if true is specified as the third 
	     *        parameter, all properties will be applied and will overwrite an 
	     *        existing property in the receiver
	     */
	    augmentProto: function(r, s) {
	        if (!s||!r) {
	            throw new Error("Augment failed, verify dependencies.");
	        }
	        //var a=[].concat(arguments);
	        var a=[r.prototype,s.prototype], i;
	        for (i=2;i<arguments.length;i=i+1) {
	            a.push(arguments[i]);
	        }
	        L.augmentObject.apply(this, a);
	    },
     
	    /**
	     * Returns a simple string representation of the object or array.
	     * Other types of objects will be returned unprocessed.  Arrays
	     * are expected to be indexed.  Use object notation for
	     * associative arrays.
	     * @method dump
	     * @since 2.3.0
	     * @param o {Object} The object to dump
	     * @param d {int} How deep to recurse child objects, default 3
	     * @return {String} the dump result
	     */
	    dump: function(o, d) {
	        var i,len,s=[],OBJ="{...}",FUN="f(){...}",
	            COMMA=', ', ARROW=' => ';

	        // Cast non-objects to string
	        // Skip dates because the std toString is what we want
	        // Skip HTMLElement-like objects because trying to dump 
	        // an element will cause an unhandled exception in FF 2.x
	        if (!L.isObject(o)) {
	            return o + "";
	        } else if (o instanceof Date || ("nodeType" in o && "tagName" in o)) {
	            return o;
	        } else if  (L.isFunction(o)) {
	            return FUN;
	        }

	        // dig into child objects the depth specifed. Default 3
	        d = (L.isNumber(d)) ? d : 3;

	        // arrays [1, 2, 3]
	        if (L.isArray(o)) {
	            s.push("[");
	            for (i=0,len=o.length;i<len;i=i+1) {
	                if (L.isObject(o[i])) {
	                    s.push((d > 0) ? L.dump(o[i], d-1) : OBJ);
	                } else {
	                    s.push(o[i]);
	                }
	                s.push(COMMA);
	            }
	            if (s.length > 1) {
	                s.pop();
	            }
	            s.push("]");
	        // objects {k1 => v1, k2 => v2}
	        } else {
	            s.push("{");
	            for (i in o) {
	                if (L.hasOwnProperty(o, i)) {
	                    s.push(i + ARROW);
	                    if (L.isObject(o[i])) {
	                        s.push((d > 0) ? L.dump(o[i], d-1) : OBJ);
	                    } else {
	                        s.push(o[i]);
	                    }
	                    s.push(COMMA);
	                }
	            }
	            if (s.length > 1) {
	                s.pop();
	            }
	            s.push("}");
	        }

	        return s.join("");
	    },

	    /**
	     * Does variable substitution on a string. It scans through the string 
	     * looking for expressions enclosed in { } braces. If an expression 
	     * is found, it is used a key on the object.  If there is a space in
	     * the key, the first word is used for the key and the rest is provided
	     * to an optional function to be used to programatically determine the
	     * value (the extra information might be used for this decision). If 
	     * the value for the key in the object, or what is returned from the
	     * function has a string value, number value, or object value, it is 
	     * substituted for the bracket expression and it repeats.  If this
	     * value is an object, it uses the Object's toString() if this has
	     * been overridden, otherwise it does a shallow dump of the key/value
	     * pairs.
	     * @method substitute
	     * @since 2.3.0
	     * @param s {String} The string that will be modified.
	     * @param o {Object} An object containing the replacement values
	     * @param f {Function} An optional function that can be used to
	     *                     process each match.  It receives the key,
	     *                     value, and any extra metadata included with
	     *                     the key inside of the braces.
	     * @return {String} the substituted string
	     */
	    substitute: function (s, o, f) {
	        var i, j, k, key, v, meta, saved=[], token, 
	            DUMP='dump', SPACE=' ', LBRACE='{', RBRACE='}',
	            dump, objstr;


	        for (;;) {
	            i = s.lastIndexOf(LBRACE);
	            if (i < 0) {
	                break;
	            }
	            j = s.indexOf(RBRACE, i);
	            if (i + 1 >= j) {
	                break;
	            }

	            //Extract key and meta info 
	            token = s.substring(i + 1, j);
	            key = token;
	            meta = null;
	            k = key.indexOf(SPACE);
	            if (k > -1) {
	                meta = key.substring(k + 1);
	                key = key.substring(0, k);
	            }

	            // lookup the value
	            v = o[key];

	            // if a substitution function was provided, execute it
	            if (f) {
	                v = f(key, v, meta);
	            }

	            if (L.isObject(v)) {
	                if (L.isArray(v)) {
	                    v = L.dump(v, parseInt(meta, 10));
	                } else {
	                    meta = meta || "";

	                    // look for the keyword 'dump', if found force obj dump
	                    dump = meta.indexOf(DUMP);
	                    if (dump > -1) {
	                        meta = meta.substring(4);
	                    }

	                    objstr = v.toString();

	                    // use the toString if it is not the Object toString 
	                    // and the 'dump' meta info was not found
	                    if (objstr === OBJECT_TOSTRING || dump > -1) {
	                        v = L.dump(v, parseInt(meta, 10));
	                    } else {
	                        v = objstr;
	                    }
	                }
	            } else if (!L.isString(v) && !L.isNumber(v)) {
	                // This {block} has no replace string. Save it for later.
	                v = "~-" + saved.length + "-~";
	                saved[saved.length] = token;

	                // break;
	            }

	            s = s.substring(0, i) + v + s.substring(j + 1);


	        }

	        // restore saved {block}s
	        for (i=saved.length-1; i>=0; i=i-1) {
	            s = s.replace(new RegExp("~-" + i + "-~"), "{"  + saved[i] + "}", "g");
	        }

	        return s;
	    },

	    /**
	     * Returns a string without any leading or trailing whitespace.  If 
	     * the input is not a string, the input will be returned untouched.
	     * @method trim
	     * @since 2.3.0
	     * @param s {string} the string to trim
	     * @return {string} the trimmed string
	     */
	    trim: function(s){
	        try {
	            return s.replace(/^\s+|\s+$/g, "");
	        } catch(e) {
	            return s;
	        }
	    },

	    /**
	     * Returns a new object containing all of the properties of
	     * all the supplied objects.  The properties from later objects
	     * will overwrite those in earlier objects.
	     * @method merge
	     * @since 2.3.0
	     * @param arguments {Object*} the objects to merge
	     * @return the new merged object
	     */
	    merge: function() {
	        var o={}, a=arguments, l=a.length, i;
	        for (i=0; i<l; i=i+1) {
	            L.augmentObject(o, a[i], true);
	        }
	        return o;
	    },

	    /**
	     * Executes the supplied function in the context of the supplied 
	     * object 'when' milliseconds later.  Executes the function a 
	     * single time unless periodic is set to true.
	     * @method later
	     * @since 2.4.0
	     * @param when {int} the number of milliseconds to wait until the fn 
	     * is executed
	     * @param o the context object
	     * @param fn {Function|String} the function to execute or the name of 
	     * the method in the 'o' object to execute
	     * @param data [Array] data that is provided to the function.  This accepts
	     * either a single item or an array.  If an array is provided, the
	     * function is executed with one parameter for each array item.  If
	     * you need to pass a single array parameter, it needs to be wrapped in
	     * an array [myarray]
	     * @param periodic {boolean} if true, executes continuously at supplied 
	     * interval until canceled
	     * @return a timer object. Call the cancel() method on this object to 
	     * stop the timer.
	     */
	    later: function(when, o, fn, data, periodic) {
	        when = when || 0; 
	        o = o || {};
	        var m=fn, d=data, f, r;

	        if (L.isString(fn)) {
	            m = o[fn];
	        }

	        if (!m) {
	            throw new TypeError("method undefined");
	        }

	        if (d && !L.isArray(d)) {
	            d = [data];
	        }

	        f = function() {
	            m.apply(o, d || NOTHING);
	        };

	        r = (periodic) ? setInterval(f, when) : setTimeout(f, when);

	        return {
	            interval: periodic,
	            cancel: function() {
	                if (this.interval) {
	                    clearInterval(r);
	                } else {
	                    clearTimeout(r);
	                }
	            }
	        };
	    },
	    
	    /**
	     * A convenience method for detecting a legitimate non-null value.
	     * Returns false for null/undefined/NaN, true for other values, 
	     * including 0/false/''
	     * @method isValue
	     * @since 2.3.0
	     * @param o {any} the item to test
	     * @return {boolean} true if it is not null/undefined/NaN || false
	     */
	    isValue: function(o) {
	        // return (o || o === false || o === 0 || o === ''); // Infinity fails
	    	return (L.isObject(o) || L.isString(o) || L.isNumber(o) || L.isBoolean(o));
	    },
	    
	    /**
	     * Return base path of the web site
	     * @method getBaseUrl
	     * @return {string} base path of the website
	     */
	    getBasePath: function(){
	    	return location.href.substr(0, location.href.search("index.php"));
	    }

	};

	/**
	 * Determines whether or not the property was added
	 * to the object instance.  Returns false if the property is not present
	 * in the object, or was inherited from the prototype.
	 * This abstraction is provided to enable hasOwnProperty for Safari 1.3.x.
	 * There is a discrepancy between ISS.lang.hasOwnProperty and
	 * Object.prototype.hasOwnProperty when the property is a primitive added to
	 * both the instance AND prototype with the same value:
	 * <pre>
	 * var A = function() {};
	 * A.prototype.foo = 'foo';
	 * var a = new A();
	 * a.foo = 'foo';
	 * alert(a.hasOwnProperty('foo')); // true
	 * alert(ISS.lang.hasOwnProperty(a, 'foo')); // false when using fallback
	 * </pre>
	 * @method hasOwnProperty
	 * @param {any} o The object being testing
	 * @param prop {string} the name of the property to test
	 * @return {boolean} the result
	 */
	L.hasOwnProperty = (OP.hasOwnProperty) ?
	    function(o, prop) {
	        return o && o.hasOwnProperty(prop);
	    } : function(o, prop) {
	        return !L.isUndefined(o[prop]) && 
	                o.constructor.prototype[prop] !== o[prop];
	    };

	// new lang wins
	OB.augmentObject(L, OB, true);
	 
	/**
	 * Same as ISS.lang.augmentObject, except it only applies prototype 
	 * properties.  This is an alias for augmentProto.
	 * @see ISS.lang.augmentObject
	 * @method augment
	 * @static
	 * @param {Function} r  the object to receive the augmentation
	 * @param {Function} s  the object that supplies the properties to augment
	 * @param {String*|boolean}  arguments zero or more properties methods to 
	 *        augment the receiver with.  If none specified, everything
	 *        in the supplier will be used unless it would
	 *        overwrite an existing property in the receiver.  if true
	 *        is specified as the third parameter, all properties will
	 *        be applied and will overwrite an existing property in
	 *        the receiver
	 */
	L.augment = L.augmentProto;

	/**
	 * An alias for <a href="ISS.lang.html#augment">ISS.lang.augment</a>
	 * @for ISS
	 * @method augment
	 * @static
	 * @param {Function} r  the object to receive the augmentation
	 * @param {Function} s  the object that supplies the properties to augment
	 * @param {String*}  arguments zero or more properties methods to 
	 *        augment the receiver with.  If none specified, everything
	 *        in the supplier will be used unless it would
	 *        overwrite an existing property in the receiver
	 */
	ISS.augment = L.augmentProto;
	       
	/**
	 * An alias for <a href="ISS.lang.html#extend">ISS.lang.extend</a>
	 * @method extend
	 * @static
	 * @param {Function} subc   the object to modify
	 * @param {Function} superc the object to inherit
	 * @param {Object} overrides  additional properties/methods to add to the
	 *        subclass prototype.  These will override the
	 *        matching items obtained from the superclass if present.
	 */
	ISS.extend = L.extend;
	
})();